|READ the directions for installing the device !|
You are often supposed to install the software for a USB modem BEFORE you plug it into a USB port !
Your computer may not be detecting the device, after the "drivers" were installed for it properly.
You may need to plug the USB modem into a different USB port.
Troubleshooting USB device problems including for flash drives, external drives, memory cards.
See Response 1:
Modem "drivers" often have associated files that must be installed properly along with the actual drivers. If you install only the actual drivers, it's likely the device will NOT work properly.
Unless the instructions for installing a device tell you otherwise......
You DO NOT install drivers for a device while booting into Windows, if the software for the device has not been installed yet - when Windows detects a generic device or New Hardware while booting, you allow it to search for drivers, it doesn't find any, and it wants you to show it the location of the drivers - CANCEL that, continue on to the desktop, and install the software for the device using the proper installation from a CD or the proper installation file that you downloaded from the web.
The same applies no matter when Windows finds New Hardware !
(The following also applies if you want to re-install the sound software)
If you DID install drivers that way, go to Control Panel - Classic View - Programs and Features and Un-install the software you installed, reboot, DO NOT install drivers while booting.
Install the software properly by running the proper download you got from the web, or if you have the CD that came with it, or if you have the CD that came with the brand name computer that has the Drivers on it, run the software installation from the installation program on that.